\item \subquestionpoints{5} Suppose we use the sigmoid function as the activation function for $h_1, h_2, h_3$ and $o$.
      What is the gradient descent update to $w_{1, 2}^{[1]}$, assuming we use a learning rate of $\alpha$?
      Your answer should be written in terms of $x^{(i)}$, $o^{(i)}$, $y^{(i)}$, and the weights.\\
      
\ifnum\solutions=1 {
  \input{01-simple_nn/01-sigmoid_sol}
} \fi
